// Copyright (C) 2013 Michael Leviston (michael.leviston@gmail.com)

// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

#ifndef ECS_NODE_H
#define ECS_NODE_H

#include <memory>
#include <map>
#include <set>

#include "Utility.h"
#include "Component.h"

namespace ECS
{
	// Pointer Definitions
	class Node;
	typedef std::tr1::shared_ptr<Node> spNode;
	typedef std::tr1::weak_ptr<Node> wpNode;

	/// \brief A node is a group of weak pointers that systems operate upon.
	///
	/// \author Michael Leviston
	class Node
	{
	public:

		/// Constructor
		Node(unsigned int ID) : id(ID) {}

		/// Destructor
		~Node() {}

		/// Get the Unique ID of this node
		unsigned int GetID() { return id; }

		/// Get the set of component IDs associated with this node
		std::set<unsigned int>& GetComponentIDs() { return componentIDs; }

		/// Add a component to the node
		unsigned int AddComponent(wpComponent wpC)
		{ 
			auto spC = ECS::MakeStrongPtr(wpC);
			unsigned int type = spC->GetType();
			unsigned int ID = spC->GetID();
			components.insert(std::pair<unsigned int, wpComponent>(type, wpC) );
			componentIDs.insert(ID);

			return ID;
		}

		/// Check if the node is associated with the component ID
		bool HasComponentID(unsigned int ID) 
		{
			auto itF = componentIDs.find(ID);
			if(itF != componentIDs.end() )
			{
				return true;
			}
			else
				return false;	
		}

		/// Get a weak pointer to the component by Type
		template <class T>
		std::tr1::weak_ptr<T> Get();

	private:

		std::set<unsigned int> componentIDs;				///< Set of component IDs associated with this node
		std::map<unsigned int, wpComponent> components;		///< Set of components associated with this node (stored by Type)
		unsigned int id;									///< Unique ID of this node
	};


	template <class T>
	std::tr1::weak_ptr<T> Node::Get()
	{
		auto findIt = components.find(T::type);
		if (findIt != components.end())
		{
			spComponent pBase(findIt->second);
			std::tr1::shared_ptr<T> pSub(std::static_pointer_cast<T>(pBase));  // cast to subclass version of the pointer
			std::tr1::weak_ptr<T> pWeakSub(pSub);  // convert strong pointer to weak pointer
			return pWeakSub;  // return the weak pointer
		}
		else
		{
			return std::tr1::weak_ptr<T>();
		}
	}

}

#endif // ECS_NODE_H